the difficulty of speaking english and maybe the other languages

I strongly believe that speaking a foreign language is very difficult situation. Because the grammar , pronounciation, and also writing of languages are extremely different from each other in all respects. Am ı right ? do you agree with me ?

I disagree with this in a very general sense. A lot of people think that learning foreign languages is a lot harder than it actually is simply because the methods being used are not correct or efficient. If you look hard enough, you will find similarities in many (unrelated, even) languages and their grammars. However, I do agree that certain languages are harder than others in different aspects (for example, although I've spoken English since I was four, I find that English has a strange pronunciation and a huge amount of idioms that are difficult even for native speakers sometimes). If the grammar is too different from your native language (like Spanish is to Russian), then it WILL be difficult and you will have to work a lot harder at it in order to get to the same level as a language like Portuguese for a Spanish speaker. So no, you don't have to COMPLETELY change your grammar or "sense of life" a lot of times, but it still is a challenging process to achieve fluency in almost any language.

I have to agree with berabero89, it is about the methods that a person uses to learn a language that will make it easier in learning it.

In my opinion English compared to other languages is more easier, in terms of grammar less easy when we talk about pronunciation. Saying that sometimes we find languages like Arabic or even German where the pronuncation is far much more complicated than English. But this is just a general opinion, and like berabero89 was saying if the grammar seems different from your native language than you will need to work very hard so that you can be at the same level as the language that you are learning.